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Studentka2010 [4]
2 years ago
5

calculate the efficiency of a light bulb that had an input of 400 j transfers 100j as a light and 300j as heat.​

Physics
1 answer:
beks73 [17]2 years ago
6 0
Efficiency = useful energy out / total energy in x 100
= 100/400 x 100
=0.25 x 100
= 25%

25%
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